1. Field of the Invention
This invention relates to a system for audibly recognizing a received signal aurally unclassifiable because it is too short or too long in its duration and/or its frequency band is too narrow or too wide. Signals of such types are conventionally received from various sensors such as infiltration radars, seismic exploration sensors, medical diagnostic apparatus, etc. More particularly, this invention relates to a system capable of analyzing a received signal and determining if the signal present is in a category of signals of interest and, if so, just what is its category within a finite number of possible a priori categories. The term "aurally unclassifiable" is used herein and in the appended claims to refer to a signal which carries information in the form in which the listener cannot determine whether or not the information is of a character, or falls in a category, of interest and, if so, in what category it falls; for example, a signal representative of object motion received by an infiltration radar.
2. DESCRIPTION OF THE PRIOR ART
No prior art apparatus similar or equivalent to that of the present invention is known although there have been proposed certain computer-oriented algorithms which can be used to perform the detection and classification of received signals. However, such methods require lengthy computer statistical learning and classification processing. As a result, real-time signal processing is neither possible with a single computer nor economical with multiple paralleled computers.
The system of the present invention may be used in substitution for the ear-brain for performing the functions of learning, detection, and subsequent classification of aurally unclassifiable signals, both economically and in real-time.